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EXHIBIT 12.1

Statement of Computation of Ratio of Earnings to Fixed Charges
(Unaudited)

	Year Ended December 31,
																Nine Months Ended September 30, 2007
	2002			2003			2004			2005			2006
(in thousands)
Earnings:
Loss before income taxes	$	(79,227	)	$	(70,583	)	$	(102,654	)	$	(143,164	)	$	(166,044	)	$	(126,939	)
Add: Fixed charges		2,325			2,032			1,855			1,818			1,881			1,379
Total Earnings	$	(76,902	)	$	(68,551	)	$	(100,799	)	$	(141,346	)	$	(164,163	)	$	(125,560	)
Fixed charges:
Interest expense	$	913		$	920		$	575		$	309		$	193		$	72
Estimated interest component of rent expense		1,412			1,112			1,280			1,509			1,688			1,307
Total fixed charges	$	2,325		$	2,032		$	1,855		$	1,818		$	1,881		$	1,379
Ratio of earnings to fixed charges		Note 1			Note 1			Note 1			Note 1			Note 1			Note 1

Note 1: Earnings for 2002, 2003, 2004, 2005, 2006 and the nine months ended September 30, 2007 were insufficient to cover fixed charges by $79.2 million, $70.6 million, $102.7 million, $143.2 million, $166.0 million and $126.9 million, respectively.

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Statement of Computation of Ratio of Earnings to Fixed Charges (Unaudited)